US Patent 7428212 Best effort technique for virtual path restoration

A method and apparatus for restoring a virtual path are disclosed. The method includes identifying an alternate physical path and determining whether the alternate physical path is able to support the virtual path by determining whether each node of the second subset of nodes has sufficient resources necessary to support the virtual path. The virtual path is over a physical path in an optical network, and the optical network includes a number of nodes. The physical path includes a first subset of nodes of the nodes. The alternate path includes a second subset of nodes of the nodes and is between a first node and a second node of the first subset of nodes.